Watch case



Oct. 27, 1959 J FlECHTER 2,909,893

WATCH CASE Filed June 14, 1955 9 United States Patent WATCH CASE Jean Jacques Fiechter, Villeret, Switzerland Application June 14, 1955, Serial No. 515,460 Claims priority, application Switzerland June 19, 1954 4 Claims. (Cl. SS-90) This invention relates to a watch case, specially adapted for use by deep-sea divers.

An object of the invention is to provide a watch case which is sufficiently leak-proof to resist the entrance of water at any depth to which a human diver may descend.

Another object is to provide such a watch case having a settable and easily visible indicator or interval timer to show the user how long he has been submerged, for

instance.

A further object is to provide such an indicator which is easy to set and yet is proof against subsequent accidental displacement.

A still further object is to provide certain improvements in the form, construction, arrangement and materials of the several parts by which the above-named andother objects may effectively be attained.

In the type of diving wherein the diver descends to considerable depths unprotected against water pressure but equipped with a portable air supply, accurate information as to the passage of time is of great importance. This is so, first, because the air supply is only designed to last for a limited time and the divers life depends on returning to the surface before the air supply is exhausted. As a second, but also vital, consideration the return from high-pressure depths to the surface must be effected gradually enough so that the body can adjust to lower pressures, without causing bends or similar serious conditions. Thus the diver must know accurately when to start his return trip, how long to take in completing it and when it must be completed.

Ordinary waterproof watches are rarely, if ever, able to withstand the pressures to which some divers are now able to descend, and ordinary luminous dials with or without interval indications-are not capable of being seen in the darkness of the depths frequently attained. These difficulties are overcome in the highly leak-proof case with clearly visible interval indicator herein disclosed. v

A practical embodiment of the invention is shown in the accompanying drawings wherein:

Fig. 1 represents a plan view of the front of the case;

Fig. 2 represents an exploded sectional view, taken on the line 11-11 of Fig. 1, on an enlarged scale;

Fig. 3 represents a sectional View corresponding to Fig. 2, with the parts assembled;

Fig. 4 represents a detail sectional view showing the indicating ring pressed into its position for free rotation and setting; and

Fig. 5 represents a detail sectional view showing a modified back structure, parts being broken away.

Referring to the drawings, the watch case comprises a main frame 1 adapted to contain the watch movement (not shown) and provided with the tubular bushing 2 for the setting and winding stem; an Oring 2' is located on the bushing in a position to seal tightly the clearance between the bushing and the interior of the stem crown 2", replacing the customary packing or the like and en- 2,909,893 Patented Oct. 27, 1959 suring water-tightness in any axial position of the. crown. On the front of the frame 1, around the dial, is provided an annular rib 3 undercut around its inner periphery to receive the beveled edge of a crystal (bonded to the case in the customary manner) and also undercut around its outer periphery to form the slanting wall 4. Outward from the base of the wall 4 the fiat surface of the frame is cut by an annular groove 5, and at the peripheral edge of the front of the frame there is formed an upwardly extending rim 6. It will be understood that the annular parts 3, 4, 5 and 6 are concentric.

The indicating ring 7 is shown as having a flat bottom surface, a cylindrical outer surface and a downwardly and inwardly tapered inner surface 7, having approximately the same angle of slope and vertical height (below the horizontal inner rim 8) as the wall 4. The smallest diameter of the surface 7' has a value between the smallest and largest diameter of said wall 4. The cylindrical outer surface of the ring 7 has a free sliding fit within the rim 6. The spring 9, which may conveniently be in the form of an undulated ring of resilient material, is of a size to fit freely in the groove 5 and to extend, in its expanded position, above the top of said groove. A plurality of small coil springs could, if desired, be substituted for the undulated spring shown. In assembling these parts, the spring 9 is placed in the groove 5 and the indicating ring 7 is snapped over the rib 3, bringing the surface 7' in a position to bear against the slanting Wall 4. The spring 9 urges the ring 7 upward to hold said surface against said wall, as shown in Fig. 3, in which position the ring is frictionally locked against rotation. When pressed toward the frame (against the spring action), as shown in Fig. 4, the ring 7 can readily be turned to any desired adjusted position.

in order to serve its purpose as an interval timer, the ring 7 is provided on its face with suitably located, prominently displayed, indicia 10 which are preferably, for the greatest security, engraved in the bottom of an annular slot 11 and covered by a protective ring 12 of transparent material, such as a clear plastic. Alternatively the indicia may be applied (as by painting or printing) to the back of the ring 12; in either case the ring provides certain and durable protection for the indicia under all conditions. The indicia 10 should comprise or be treated with reflecting or luminescent material in order to have the highest possible visibility even in the obscurity of deep water.

The back of the frame 1 is provided with a groove 13 in which is seated a sealing ring 14 (preferably O-ring). A back plate 15 has a peripheral flat surface 15' adapted to bear against the ring 14. The back plate is held firmly in place by the lock ring 16 which engages it and is screwed onto the frame by means of the threads 17.

In operation, it is intended that the diver shall, at the beginning of his dive, set the Zero point of the ring 7 opposite the (luminous) minute hand of the watch. Thereafter, at any time during the first hour (or subsequent hours, if necessary) the elapsed time of submergence can be read at a glance without need for calculations of any kind. The indicia on the indicating ring can easily be made large and clear, because the ring is necessarily larger than the face of the watch which it surrounds. Accidental movement of the ring is extremely unlikely; even if one side of it is depressed and so released. The frictional engagement of the slanting surfaces on the opposite side wall will remain effective to prevent rotation, which can only be effected when the ring is pressed in all the way around. It will be noted that the movability of the ring has no effect on the watertight sealing of the case itself, which is adequate to pre- 3 ventthe penetration. of moisture at all depths (andpressures) in which the watch may be worn.

In the modified back structure shown in Fig. 5, the outer back plate 18 is given progressively increasing. supportagainst highipressures (such as 'water pressure at great depths) 'by the provision of aidomed inner back plate 1?, the peripheral edge of which is seated in the rabbet 2%} of the main frame and the center of which rests lightly against the center of the plate 18. Upon deformation of the latter under pressure (dot-dash lines), the plate 19 resists strongly and increasingly, while also providing, at its periphery, a second very tight seal against leakage. (The deformation shown is exaggerated.)

It will be understood that variouschanges may be made in the construction, form and arrangement of the several parts without departing from the scope of my invention and hence I do not intend to be limited to the particular embodiment herein shown and'described except as set forth in the appended claims.

It isclear that, for instance, the above described indicating ring can also be fixed on a stop watch for airmen or on a chronograph in order to indicate more clearly the elapsed time even in darkness.

What I claim is:

1. A watch case comprising, a main frame having front and back openings and a space for the watch movement, a back plate secured to the back of the frame to water-tightly close the back opening, a crystal secured to the front of the frame to water-tightly close the front opening, an indicating ring rotatably mounted on the front of said frame and bearinghigh-visibility indicia, and manually releasable-means for locking said ring against rotation, said frame and said indicating ring being provided with complementary continuous annular non- 4 cylindrical surfaces, and said releasable meansincluding a spring located between the frame and the ring and acting to urge the ring in a direction to bring said surfaces into engagement.

2. A watch case according to claim 1 in which the noncylindrical surface on the frame is approximately frustoconical and overlies a co 'plementary frusto-conical surface on the ring.

3. A watch case according to claim 2 in which the frusto-conical Surface'on the frameforms the'outer wall of an annular rib on the front of the .case'and in which the maximum diameter of said surface is. greater than the minimum diameter of the complementarysurface'on the indicating ring.

4. A watch case according to claim 1 in which the front of the frame is provided with an annular groove having a free fit with the indicating ring and inwhich the 'springrests in said groove.

References Cited in the file of this patent UNITED STATES PATENTS 1,322,770 Eastwood Nov. 25,1919 2,332,459 Muney et al Oct. 19, 1943 2,341,271 Ditesheim Feb.8', 1944 2,462,839 Brown Mar. 1, 1949- 2,716,829 Huguenin Sept. '6, 1955 i 1 2,733,567 Zellweger Feb. 7, 1956 2,736,164 Piquerez Feb. 28, 1956 FOREIGN PATENTS 239,785 Switzerland June 17, 1946 258,776 Switzerland May 16, 1949 281,492 Switzerland June 16,1952 

